Prilocaine

Local anesthetic of the amino amide type

EU EMA: by INN
US DailyMed: Prilocaine

Pregnancy
category

AU: A

Routes of
administrationSubcutaneousATC code

N01BB04 (WHO)

AU: S4 (Prescription only)
US: ℞-only

Pharmacokinetic dataProtein binding55%MetabolismLiver and kidneyElimination half-life10-150 minutes, longer with impaired liver or kidney functionIdentifiers

IUPAC name

(RS)-N-(2-methylphenyl)-N²-propylalaninamide

CAS Number

721-50-6^Y

PubChem CID

4906

IUPHAR/BPS

7276

DrugBank

DB00750^Y

ChemSpider

4737^Y

UNII

046O35D44R

KEGG

D00553^Y
as HCl: D01243^Y

ChEBI

CHEBI:8404^Y

ChEMBL

ChEMBL1194^Y

CompTox Dashboard (EPA)

DTXSID7031955

ECHA InfoCard100.010.871

Chemical and physical dataFormulaC₁₃H₂₀N₂OMolar mass220.316 g·mol⁻¹3D model (JSmol)

Interactive image

ChiralityRacemic mixture Melting point37 to 38 °C (99 to 100 °F)

SMILES

O=C(Nc1ccccc1C)C(NCCC)C

InChI

InChI=1S/C13H20N2O/c1-4-9-14-11(3)13(16)15-12-8-6-5-7-10(12)2/h5-8,11,14H,4,9H2,1-3H3,(H,15,16)^Y
Key:MVFGUOIZUNYYSO-UHFFFAOYSA-N^Y

(verify)

Prilocaine (/ˈpraɪləˌkeɪn/^[1]) is a local anesthetic of the amino amide type first prepared by Claes Tegner and Nils Löfgren. In its injectable form (trade name Citanest), it is often used in dentistry. It is also often combined with lidocaine as a topical preparation for dermal anesthesia (lidocaine/prilocaine or EMLA), for treatment of conditions like paresthesia. As it has low cardiac toxicity, it is commonly used for intravenous regional anaesthesia (IVRA).

Contraindications

In some patients, ortho-toluidine, a metabolite of prilocaine, may cause methemoglobinemia, which may be treated with methylene blue. Prilocaine may also be contraindicated in people with sickle cell anemia, anemia, or symptomatic hypoxia.^[2]

Combinations

It is given as a combination with the vasoconstrictor epinephrine under the trade name Citanest Forte. It is used as a eutectic mixture with lidocaine, 50% w/w, as lidocaine/prilocaine. The mixture is an oil with a melting point of 18 °C (64 °F). A 5% emulsion preparation, containing 2.5% each of lidocaine/prilocaine, is marketed by APP Pharmaceuticals under the trade name EMLA (an abbreviation for eutectic mixture of local anesthetics).^[3]

Compendial status

United States Pharmacopeia 31 ^[4]

Synthesis

The amidation between o-toluidine [95-53-4] (1) and 2-bromopropionyl bromide [563-76-8] (2) leads to 2-bromo-N-(2-methylphenyl)propanamide [19397-79-6] (3). Displacement of the remaining halide with propylamine [107-10-8] (4) completed the synthesis of prilocaine (5).

References

^ "Prilocaine". Merriam-Webster.com Dictionary. Retrieved 2016-01-21.
^ Patel V, Morrissey J (2011-09-15). Practical and Professional Clinical Skills. Oxford University Press. p. 267. ISBN 9780199585618.
^ "Topical Anesthesia Use in Children: Eutectic Mixture of Local Anesthetics". Medscape.com. Retrieved 2014-01-07.
^ The United States Pharmacopeial Convention, Revision Bulletin: Lidocaine and Prilocaine Cream–Revision to Related Compounds Test, archived from the original on 5 July 2010, retrieved 10 July 2009
^ Löfgren, Nils; Tegnér, Claës; Arwidsson, Barbro; Varde, E.; Westin, Gertrud (1960). "Studies on Local Anesthetics. XX. Synthesis of Some alpha-Monoalkylamino-2-methylpropionanilides. A New Useful Local Anesthetic.". Acta Chemica Scandinavica 14: 486–490. doi:10.3891/acta.chem.scand.14-0486.
^ Anon., GB 839943 (to Astra Apotekarnes Kem Fab).
^ Lofgren Nils Magnus, Tegner Claes Philip, U.S. patent 3,160,662 (1964 to Astra Apotekarnes Kem Fab).
^ Demare, Patricia; Regla, Ignacio (2012). "Synthesis of Two Local Anesthetics from Toluene: An Organic Multistep Synthesis in a Project-Oriented Laboratory Course". Journal of Chemical Education. 89 (1): 147–149. doi:10.1021/ed100838a.
^ 沈文晖, 杨忠鑫, 葛小强, 张宇生, 邹玉龙, 张强, 杨继斌, 蔡中文, CN 105439887 (2016 to 重庆康乐制药有限公司).

External links

"Prilocaine". Drug Information Portal. U.S. National Library of Medicine.
"Prilocaine hydrochloride". Drug Information Portal. U.S. National Library of Medicine.

Local anesthetics (primarily sodium channel blockers) (N01B)

Esters by acid

Aminobenzoic	Benzocaine Benzonatate Butacaine Butamben Chloroprocaine Dimethocaine Lucaine Meprylcaine Metabutethamine Metabutoxycaine Nitracaine Orthocaine Propoxycaine Procaine (Novocaine) Proxymetacaine Risocaine Tetracaine
Benzoic	Amylocaine Cocaine Cyclomethycaine α-Eucaine β-Eucaine Hexylcaine Isobucaine Piperocaine
ArCO2- (not para-amino or Ph)	Amoproxan (3,4,5-Trimethoxybenzoyl) 3-(p-Fluorobenzoyloxy)tropane